The moment you see The Trophy you are glad it is inside a glass case. It's a complex kinetic sculpture, bearing a passing resemblance to the pictures of the machine which was recently sent on a jaunt up to Mars to discover signs of life. This alarming robot is the goddess Diana who, in Titian's Diana and Acteon, is distressed and vulnerable, having been spied upon by the unfortunate Acteon while bathing with her nymphs. In a later painting, The Death of Acteon, she exacts a terrible revenge: he is transformed into a stag, then torn to pieces by his own hounds. Here he is represented by a bare antler carved out of wood.
The light at the end of a probe is unnerving: it spirals and judders and swoops. At times 'Diana' seems to be preening and caressing herself, beguiling, almost flirtatious.Then the probe swings out towards Acteon, now teasing and playful. But the mood changes. It becomes menacing and monstrous. Acteon cannot flinch or move. Then another switch - she seems content, as if conducting an impartial post mortem on her miserable victim.
I'm aware that attributing human motives to non humans is something I've tried to avoid all my life. But, as the person I was with said, 'robots are to art this year what 3D printing was to art in 2011'. You have to see to believe.
The centrepiece of the exhibition is a shadowy room which feels a bit like a corridor. It's hard to stay there with these three momentous Titians - Diana and Callisto, Diana and Acteon and The Death of Acteon. They need time and a good light but time is nibbled away by curiosity as to how three living artists have responded in the adjoining rooms. As well as Shawcross's Trophy, Chris Offilli's beautiful paintings in breathtaking colours transpose the classical world to Trinidad; and Mark Wallinger invites us to invade the goddess Diana's private space once again by peeping (one-eyed like the probe) into her bathroom.
Metamorphosis is a remarkable exhibition. A bit of a fairground. To celebrate the bringing together of these three Titian paintings, (two of which have been recently acquired), the help of not only artists but choreographers, composers, musicians, designers and poets has been called upon. We are invited to listen to poetry as well as inspect costumes, installations, set designs, paintings.
On the way out is the small gallery cinema showing clips from the ballets and a number of poets reading their specially commissioned work. (Patience Agabi, Christopher Reid, Seamus Heaney and Sinead Morrissey are the poets who get my vote). You can buy a beautifully illustrated book of the poems together with an essay on Ovid, Titian and English Poetry, and images of all three Titian paintings.
Metamorphosis: poems inspired by Titian, published by The National Gallery, only £8.
You can also get a stunning image of Trophy, of the Titian paintings, and much much more if you follow the links on nationalgallery.org.uk